Optical Ftber Length Measurement By External Phase Modulatton Type Optical Heterodyne Reflectometry

摘要

An optical fiber length measuring method using an external phase modulation type reflectometry is proposed and experimentally-demonstrated. Use of a gas laser light source and external fiber phase modulator exclude destabilizing effect of direct modulation scheme. Typical experimental results of fiber length measurements by changing its length stepwise indicate high agreement with real length.